Your shopping cart

How does GPS work?

Digital maps

How does digital mapping work?

Keeping digital maps up to dateThere are 3 main ways to collect the data to develop and update digital maps:

1. Fieldwork. Data collectors driving the road networks of the world, recording changes and discrepancies.2. Analysis of aerial and satellite imagery.3. Customer feedback. At TomTom, for example, any map feedback from customers via the website are reported to TeleAtlas, who look into every single case and , where appropriate, actually send inspectors out to physically check the locations.

Digital mapping is a time-consuming and logistically challenging process. So a company like TeleAtlas is constantly developing new technologies and practices to increase the speed and comprehensiveness with which their maps are updated.

Take fieldwork. TeleAtlas have now also developed mobile mapping systems.

Mobile Mapping systems – a little bit James Bond Mobile Mapping vans are equipped with up to six high-resolution digital cameras, with at least one pair operating stereoscopically. This means that two cameras are spaced apart, so that their combined images provide 3-D information.

The vans also carry a differential GPS receiver, fibre-optic gyro, odometer and up to 4 PC’s equipped with tailor-made programming to process data on board.

It means TeleAtlas can build up a library of information and, more importantly, that your TomTom maps are updated to reflect changes in the real world as soon as possible after they occur.

One measure of this is the fact that over half the feedback of map discrepancies TomTom now receives from customers have already been resolved before the complaint arrives.

More map for your megabyteBut the basic principles of mapping have never really changed. Whether they were using drawings or sea shells, the earliest map makers were effectively compressing information about the real world onto something thousands of times smaller than that real world. The difference is scale.

What makes digital mapping viable is the efficiency with which data is compressed. We tend to become very blasé nowadays about technological achievement, but if you stop to think for a minute, it is quite amazing that you can have all the roads of Europe contained on a card the size of your thumbnail.

The future of digital mappingThere are probably two main areas where advances are being made in ways that are important to make getting from A to B even easier.

The first is in the quality of the maps themselves. Enhanced visualisation should enhance your driving experience. In particular areas like 3D, elevation models and landmarks, have enormous potential.

The other is in a technology called 'incremental updating'. Basically this means that only that part of the database that is added, deleted or modified, is handed onto you; the map user. Which could help greatly in the constant battle to reduce the delay between changes occurring out there on the roads and those changes appearing on your map.

Myth Busters

Myth Busters

Truth: GPS signals cannot be received under water and are blocked by large, solid structures. They can be received in open air and through glass/windows. So you may sometimes pick up a signal inside a building, depending on where you’re standing in relation to windows and other openings to the sky.

Please enable Javascript to enjoy this site.

You need to have Javascript enabled in your browser to use this site.

Your browser's help feature will be able to help you futher to enable Javascript.